DE102007045385B3 - A method for shortening or extending a viewing distance between the viewer and an arrangement for spatially perceptible presentation - Google Patents

Abstract

The invention relates to the field of spatial representation, in particular the spatially perceptible presentation without aids for simultaneously multiple viewers, the so-called autostereoscopic visualization. The invention has for its object to provide a way to autostereoscopic display, allowing an adjustment of the viewing distance regardless of constraints on the design of the distance from the image display device to the optical element, such as barrier or lenticular. This object is achieved by a method for spatial representation in which image information of different views A (k) with k = 1,..., N and n> = 2 is visible on a grid (1) of picture elements x (i, j) wherein on each picture element x (i, j) only the picture part information of exactly one of the views A (k) is made visible, the grid (1) of picture elements x (i, j) has at least one optical element (2). or subordinate, wherein according to the invention the viewing distance w and the mean distance s between the at least one optical element (2) and the grid (1) of picture elements x (i, j) are selected independently of each other.

Description

method for shortening or extension a viewing distance between the viewer and an arrangement to the spatially perceptible representation The invention relates to the field the spatial Representation, in particular of spatially perceptible without aids Presentation for at the same time several observers, the so-called autostereoscopic Visualization.

For some time, there have been approaches to the aforementioned subject area. A pioneer in this field was Frederic Ives, who in Scripture GB190418672 A A system with a "line screen" for the 3D representation presented.In addition, in the writing by Sam H. Kaplan "Theory of parallax barriers", Journal of SMPTE Vol. 59, No 7, pp 11-21, July 1952 fundamental findings on Use of barrier screens for the 3D representation described.

For a long time, however, no comprehensive dissemination of autostereoscopic systems was achieved. Only in the 80s of the 20th century could a certain renaissance of the 3D systems be used due to the now available computing power and new display technologies. In the 1990s, the number of patent applications and publications on glasses-free 3D visualizations skyrocketed. Outstanding results have been achieved by the following inventors or providers:
In the JP 08-331605 AA describe Masutani Takeshi et al. (Sanyo) a step barrier in which a transparent barrier element has approximately the dimensions of a color subpixel (R, G or B). With this technique, it was possible for the first time to partially redirect the vertical resolution of the loss of resolution in the horizontal direction that occurs in most autostereoscopic systems due to the simultaneous display of several views (at least two, preferably more than two views). The disadvantage here, as with all barrier methods, is the high loss of light. In addition, when the viewer moves sideways, the stereo contrast changes from nearly 100% to about 50%, and then increases again to 100%, resulting in a 3D image quality that fluctuates in the viewing space.

Pierre Allio succeeded in teaching after the US 5,808,599 A . US 5,936,607 A and WO 00/10332 A1 a noteworthy evolution of lenticular technology, using a sub-pixel-based view layout as well.

Another outstanding result was presented by Cees van Berkel with the EP 0 791 847 A1 patent pending. Lenticular lenses inclined relative to the vertical are located above a display which also shows different perspective views. Characteristically n views are divided on at least two screen lines, so that in turn the loss of resolution from the horizontal is partially transferred to the vertical.

However, lenticular lenses are expensive to produce and the production process for a 3D display based on them is not trivial. Jesse Eichenlaub founded several of the milestones for autostereoscopy with the writings US 6,157,424 A and WO 02/35277 A1 as well as several other inventions, however, which represent almost all 3D systems for only one viewer and / or are often not manufacturable at acceptable cost.

With the DE 10 003 326 C2 succeeded Armin Grasnick et al. a further development of the barrier technology with respect to two-dimensionally structured wavelength-selective filter arrays to produce a 3D impression. However, the disadvantage here too is the greatly reduced brightness of such 3D systems compared with a 2D display. Armin Schwerdtner succeeded with the WO 2005/027534 A2 a novel technological approach for a full-resolution 3D rendering in all (usually two) views. However, this approach is associated with high adjustment effort and for larger screen diagonals (from about 25 inches) is extremely difficult to implement.

Finally, Wolfgang Tzschoppe et al. the WO 2004/077839 A1 which relates to a brightness-enhanced barrier technology. Based on the approach of a step barrier of JP 08-331605 AA as well as the DE 10 003 326 C2 Here, a special duty cycle of the transparent to the opaque barrier filter elements is presented, which is greater than 1 / n with n the number of views shown. However, the embodiments and teachings disclosed in this document generally produce unpleasant moiré effects and / or greatly limited depth perception, since the stereo contrast - compared with about the teaching of the JP 08-331605 AA - is greatly reduced.

The DE 101 45 133 C1 teaches displaying image part information in more than one view in an image rendering element. By virtue of this method, it is also possible to change the viewing distance via image manipulation. The disadvantage here is the mixing of the image information in the image display elements, which degrades the 3D channel separation and in the image, both contrast and sharpness greatly reduced in part.

Farther is disadvantageous in the 3D systems in the prior art because of the close relationship between pixel size, viewing distance and Distance of the parallax barrier screen to the imager (see also the equations (1) and (2) in the above-mentioned Kaplan article) often too big optimal 3D viewing distance is produced. This is especially the case when, on the one hand, very small image display elements (usually color subpixels) are present and on the other hand at the same time the mechanical design of an imager a relatively large one Distance of the imager to the barrier screen requires, for example, if a LCD panel in one relatively thick Metal frame is bordered, on which a barrier screen glued shall be. Although then the perceived 3D depth impression is particularly large, but the usability of such a system is severely limited because the minimum required 3D viewing distance required is practical is clearly too big.

Of the The invention is therefore based on the object, a possibility to create autostereoscopic presentation, which is an adaptation the viewing distance independently of constraints for the Designing the distance from the image display device to the optical element, such as allow about barrier or lenticular.

• – auf einem Raster aus Bildelementen x(i, j) mit Zeilen i und Spalten j Bildteilinformationen verschiedener Ansichten A(k) mit k = 1, ..., n und n >= 2 sichtbar gemacht werden, wobei auf jedem Bildelement x(i, j) ausschließlich eine Bildteilinformation genau einer der Ansichten A(k) sichtbar gemacht wird, und
• – dem Raster aus Bildelementen x(i, j) im Abstand s mindestens ein optisches Element mit periodisch angeordneten optischen Stukturen vor- oder nachgeordnet wird, welches für das von den Bildelementen x(i, j) transmittierte oder ausgestrahlte Licht die Ausbreitungsrichtungen vorgibt,
• – die durchschnittliche horizontale und/oder vertikale kleinste Periodenlänge oder ein Vielfaches davon der optischen Strukturen auf dem mindestens einen optischen Element ein ganzzahliges Vielfaches der durchschnittlichen horizontalen und/oder vertikalen Abmessung eines Bildelementes x(i, j) multipliziert mit einem Korrekturfaktor f beträgt,
• – wobei der Korrekturfaktor f als eine Funktion eines wählbaren Betrachtungsabstandes w und des mittleren Abstandes s zwischen dem mindestens einen optischen Element und dem Raster aus Bildelementen x(i, j) errechnet wird,
• – so dass ein oder mehrere Betrachter beim Blick auf das Raster auf Grund der optischen Wirkung des mindestens einen optischen Elements jeweils mit beiden Augen ausschließlich oder überwiegend unterschiedliche Bildelemente x(i, j) und/oder Teile davon sieht bzw. sehen, wodurch beide Augen jeweils ausschließlich oder überwiegend unterschiedliche Ansichten A(k) wahrnehmen und damit ein räumlicher Seheindruck entsteht,

dadurch gelöst, dass der Betrachtungsabstand w verkürzt wird, indem die Ungleichung s/ha > w/pa eingestellt wird, wobei die durchschnittliche horizontale Abmessung ha eines Bildelementes x(i, j), der mittlere Abstand s zwischen dem mindestens einen optischen Element und dem Raster aus Bildelementen x(i, j) sowie der mittlere Pupillenabstand pa nicht verändert werden, jedoch durch gezielte Änderung des Korrekturfaktors f die durchschnittliche horizontale kleinste Periodenlänge der optischen Struktur verkleinert wird, oder dass der Betrachtungsabstand w verlängert wird, indem Ungleichung s/ha < w/pa eingestellt wird, wobei der mittlere Abstand s zwischen dem mindestens einen optischen Element und dem Raster aus Bildelementen x(i, j) sowie der mittlere Pupillenabstand pa ebenfalls nicht verändert werden, jedoch durch gezielte Änderung des Korrekturfaktors f die durchschnittliche horizontale kleinste Periodenlänge der optischen Struktur vergrößert wird. Das vorgenannte gilt für den Fall, dass sich das optische Element in Betrachtungsrichtung vor dem Raster aus Bildelementen befindet, anderenfalls würde jeweils die kleinste Periodenlänge der optischen Struktur entsprechend gerade umgekehrt verändert, nämlich vergrößert bzw. verkleinert. Allgemein geht die horizontale Vergrößerung/Verkleinerung der kleinsten Periodenlänge der optischen Struktur auch mit einer durch den Korrekturfaktor f bedingten vertikalen Vergrößerung/Verkleinerung der kleinsten Periodenlänge der optischen Struktur einher.According to the invention, the object with a method for shortening or extending a viewing distance between the viewer and the arrangement of a spatially perceptible representation in which

• On a grid of picture elements x (i, j) with rows i and columns j, picture partial information of different views A (k) with k = 1,..., N and n> = 2 are made visible, whereby on each picture element x ( i, j) only a partial image information of exactly one of the views A (k) is made visible, and
• At least one optical element with periodically arranged optical structures, which predefines the propagation directions for the light transmitted or emitted by the picture elements x (i, j), is spaced at a distance s from the grid of picture elements x (i, j),
• The average horizontal and / or vertical smallest period length or a multiple thereof of the optical structures on the at least one optical element is an integer multiple of the average horizontal and / or vertical dimension of a picture element x (i, j) multiplied by a correction factor f,
• The correction factor f being calculated as a function of a selectable viewing distance w and of the average distance s between the at least one optical element and the grid of picture elements x (i, j),
• - So that one or more viewers when looking at the grid due to the optical effect of the at least one optical element with two eyes exclusively or predominantly different pixels x (i, j) and / or see parts thereof or see, whereby both eyes perceive exclusively or predominantly different views A (k) and thus create a spatial visual impression,

in that the viewing distance w is shortened by setting the inequality s / ha> w / pa, wherein the average horizontal dimension ha of a picture element x (i, j), the average distance s between the at least one optical element and the Raster of picture elements x (i, j) and the average pupil distance pa are not changed, but by targeted change of the correction factor f, the average horizontal smallest period length of the optical structure is reduced, or that the viewing distance w is extended by inequality s / ha < w / pa is set, wherein the average distance s between the at least one optical element and the grid of pixels x (i, j) and the average pupillary distance pa are also not changed, however, by targeted change of the correction factor f, the average horizontal smallest period length the optical structure is increased. The above applies to the case where the optical element is located in the viewing direction in front of the grid of picture elements, otherwise the smallest period length of the optical structure would in each case be changed, ie increased or reduced, correspondingly just inversely. Generally, the horizontal enlargement / reduction of the smallest period length of the optical structure is also accompanied by a vertical enlargement / reduction of the smallest period length of the optical structure caused by the correction factor f.

The average horizontal and / or vertical least period length of the optical structures on the at least one optical element Let's define here as average horizontal or vertical Distance from a point on an optical structure to an identical one Point in horizontal or vertical direction, which is to the next adjacent belongs to optical structure.

Of the mean distance s between the at least one optical element and the grid of picture elements x (i, j) is understood in particular as a mean distance between an optically effective surface or Plane of the optical element and the imaging surface of a Rasters of picture elements x (i, j).

Of the Viewing distance w is to be understood in particular as the distance the optically effective surface or plane of the optical element to a viewer eye. Though There are in process according to the invention equal to several possible Viewing distances, however, one of them is the excellent (optimal) viewing distance w.

The correction factor f is preferably calculated according to the equation f = w / (w + s). The particular advantage of the invention is that the excellent viewing distance w of one or more observers over the prior art can be reduced by setting the inequality s / ha> w / pa, the average distance s between the at least one optical element and the grid of picture elements x (i, j) and the average pupillary distance pa, which is known to be predetermined by nature, are not changed, but the average horizontal smallest period length of the optical structure is reduced by targeted modification of the correction factor f. Thus, it is also possible to arrange the optical element at a relatively large distance s from the grid of picture elements x (i, j), without forcibly taking too large a viewing distance w into account. The embodiment of the correction factor f according to the invention then ensures that a practically acceptable viewing distance w is nevertheless realized, without - as in the prior art necessary - having to make any manipulations on the image content, such as in the DE 101 45 133 C1 described.

It is self-evident also possible, that the excellent viewing distance w of one or more Viewer opposite be increased in the prior art can by taking the inequality s / ha <w / pa is set, the average horizontal dimension ha of a picture element x (i, j), the mean distance s between the at least one optical element and the grid of picture elements x (i, j) as well as the mean pupillary distance pa also do not change, however, through targeted change of the correction factor f the average horizontal smallest period length the optical structure is increased. This application should in practice rather rare application find, however, is particularly according to the invention easy to implement.

henceforth The picture elements x (i, j) correspond in each case to individual color subpixels (R, G or B) or clusters of color subpixels (eg RG, GB or RGBR or other) or full color pixels, with full color pixels both white blending Formations of RGB color subpixels, ie RGB triplets, as well as - depending on Imaging technology - actual Full color pixels - like about common in projection screens - meant are.

In an advantageous embodiment of the method is the optical Element is a parallax barrier screen used as optical structures includes transparent and opaque sections, roughly in the form of smooth or wavy Strip or step-shaped Stairs, as suggested in some documents mentioned above.

It but it is also possible that the optical element is a lenticular screen, which is optical Structures cylindrical lenses includes.

In usually correspond to the views in the process of the invention A (k) each different perspectives of a scene / an object. It can but also parallel projections of a scene or otherwise projected Be views.

at the method according to the invention the arrangement of the image part information of different views takes place A (k) on the grid of picture elements x (i, j) advantageously in one two-dimensional periodic pattern, the period length in the horizontal and vertical direction preferably not more than each 32 pixels x (i, j) comprises. Exceptions to this limit Of every 32 picture elements x (i, j) are of course permitted. Prefers is the vertical period length equal to the number n of views shown.

usually imprisonment should be the angle which the said horizontal and vertical period length spans the said two-dimensional periodic pattern as a counter and ankate catheter, essentially the angle of inclination of the transparent sections on the parallax barrier screen (if such, the optical element is) opposite correspond to the vertical. This will provide the best channel separation reached the 3D presentation.

In a first embodiment of the arrangement used in the method For example, the optical element is a parallax barrier screen used as optical Structures includes transparent and opaque sections. Prefers the transparent sections correspond to smooth or stepped lines, which is essentially at an angle of inclination a to the Vertical are inclined. For the size of the angle of inclination a there is no restriction. It is therefore explicitly not possible to lean towards the vertical.

Further it is possible in a second embodiment that the optical element a lenticular screen is the cylindrical structures as optical structures includes. Even then, preferably, the cylindrical lenses are substantially with a tilt angle a opposite arranged vertically. The inclination angle a can also be all here Accept values, so that here too no inclination towards the Vertical possible is.

Further Embodiments of the arrangement with respect to the optical elements, with holographic-optical elements, are conceivable.

When Image display device preferably a color LCD screen, a plasma display, a projection screen, an LED-based screen, an OLED-based screen, a SED screen or a VFD screen.

Farther For example, the number n of views A (k) is equal to 4, 5, 6, 7, 8 or 9 and the said horizontal period length corresponds by way of example n picture elements x (i, j). The number n of views A (k) can also be larger or be smaller than stated here.

For the embodiment of the optical element as Parallaxenbarriereschirm the following details are favorable:
In order to arrive at practically producible arrangements, the parallax barrier screen preferably consists of a glass substrate to which the barrier structure is applied on the rear side. Other configurations are possible, such as substrates that are not made of glass (eg plastic). Preferably, the barrier structure is now an exposed and developed photographic film laminated on the backside of the glass substrate, preferably the emulsion layer of the photographic film facing the glass substrate. On the other hand, it is also possible that the opaque regions of the barrier structure are formed by ink printed on the glass substrate.

henceforth contains the parallax barrier screen advantageously means for reducing of flare reflections, preferably at least one interference-optical antireflection coating. It can but also usual Antiglare mattings are used.

Of the Parallax barrier screen is advantageous by means of a spacer permanently attached to the image display device, for example glued or screwed on. In contrast, it may also be necessary be temporarily removable from the image display device, the parallax barrier screen to design.

The Invention will be explained below with reference to exemplary embodiments. The drawings show:

1 the schematic structure for implementing the method according to the invention,

2 a sketch of a parallax barrier screen for use in the method according to the invention,

3 an exemplary image combination of the image part information of different views

4 an illustration of the effect according to the invention, wherein the viewing distance is increased,

5 an illustration of the effect according to the invention, wherein the viewing distance is reduced,

6a and 6b a sketch to explain the increase of the depth impression in the case of reducing the viewing distance,

7 a section of a parallax barrier screen to illustrate its essential characteristics.

All Drawings are not to scale. This especially concerns angle measurements.

So first, point 1 the schematic structure for implementing the method according to the invention.

It contains a grid 1 from picture elements x (i, j), on which picture part information of different views A (k) with k = 1, ..., n and n> = 2 are made visible, wherein on each picture element x (i, j) only the picture part information exactly one of the views A (k) is made visible.

The grid 1 from picture elements x (i, j) is at a distance s in the viewing direction of a viewer 3 at least one optical element 2 with substantially periodically arranged optical structures which predetermines propagation directions for the light transmitted or emitted by the picture elements x (i, j). In this example, exactly one optical element 2 present, which as parallax barrier screen 2 is executed. Needless to say, there are also several viewers 3 be, who gain a spatial impression due to the method according to the invention.

Further shows 2 the section of a parallax barrier screen 2 for exemplary use in the process according to the invention. This parallax barrier screen 2 contains alternately opaque and transparent sections, wherein the transparent sections according to the invention correspond to substantially rectilinear lines. The transparent and opaque sections are arranged recurring periodically, they correspond to the optical structures on the parallax barrier screen 2 , Now their average horizontal and vertical least period length is an integer multiple of the average horizontal and vertical dimensions of a picture element x (i, j) multiplied by a correction factor f, the correction factor f being a function of a selectable viewing distance w and the distance s between the optical element 2 and the grid 1 is calculated from pixels x (i, j).

Furthermore there 3 an example image combination of the image part information of example five different views A (k) with k = 1, ..., 5 again. In the method according to the invention, the arrangement of the image part information of different views A (k) takes place on the grid 1 of pixels x (i, j) advantageously in a strictly two-dimensional periodic pattern. In the example according to 3 the horizontal period length eight and the vertical period length six pixels x (i, j), identified as a dashed frame. At the same time, the image part information for each picture element x (i, j) is derived from the position (i, j) from the corresponding view A (k).

In The exemplary embodiment presented here corresponds to the vertical period length So not the number n = 5 of the views shown.

Due to the visual confinement effect of the parallax barrier screen 2 see or see one or more viewers 3 each with two eyes substantially different picture elements x (i, j) and / or parts thereof, whereby both eyes each perceive substantially different views A (k) and thus creates a spatial visual impression. To a certain extent, the two eyes of one and the same observer can do so 3 even see partial image information of the same view A (k) without destroying the spatial impression.

henceforth The picture elements x (i, j) correspond in each case to individual color subpixels (R, G or B).

The circumstances after the 1 to 3 Assuming now according to the invention the (optimal or selected) viewing distance w and the distance s between the optical element 2 , So the parallax barrier screen, and the grid 1 selected from pixels x (i, j) independently of each other. In particular, both quantities w and s are not related to one another by a predetermined value for the eye relief or / and the dimension of a pixel x (i, j), as is conventional in the prior art.

Of the Correction factor f is calculated according to the equation f = w / (w + s).

In usually correspond to the views in the process of the invention A (k) each different perspectives of a scene / an object. It can but also parallel projections of a scene or otherwise projected Be views.

The angle which spans the said horizontal and vertical period length of the said two-dimensional periodic pattern as counter and adjacent part essentially corresponds to the angle of inclination a (see FIG 2 ) of the transparent portions on the parallax barrier screen 2 opposite the vertical. In 3 For example, the opposing catheter could be defined by the lower horizontal dashed line and the adjacent catheter by the right vertical dashed line.

In order to will usually be the best channel separation in 3D rendering reached.

In 4 is an illustration of the effect according to the invention to see in which the viewing distance w is increased over the prior art. In this case - without this being directly recognizable from the drawing - for the viewing distance w of one or more observers 3 , the distance s between the parallax barrier screen 2 and the grid 1 From pixels x (i, j), the average pupillary distance pa and the average horizontal dimension ha of a pixel x (i, j), the inequality s / ha <w / pa. The dashed lines clearly show how the conditions are in the prior art. There, the inequality does not apply.

In contrast, in 5 to see an illustration of the effect according to the invention, in which the viewing distance w of one or more observers 3 is reduced compared to the prior art.

This results in particular advantages of the invention. In this case - without this being directly recognizable from the drawing - for the viewing distance w, the distance s between the parallax barrier screen 2 and the grid 1 From pixels x (i, j), the average pupillary distance pa and the average horizontal dimension ha of a pixel x (i, j), the inequality s / ha> w / pa.

In this application, namely, the optical element or the Parallaxenbarriereschirm 2 be arranged at a relatively large distance s from the grid of picture elements x (i, j). The embodiment of the correction factor f according to the invention ensures that a practically acceptable viewing distance w can nevertheless be realized, without having to make any manipulations on the image content.

Also Here, the dashed lines indicate how the conditions in the prior art BE REDUCED. It can be clearly seen that the inventive method the viewing distance w reduces it to a practically relevant area.

The 6a and 6b each show a sketch to explain the increase of the depth impression in the case of reducing the viewing distance. It is in 6a to see how a large perceived depth t1 is achieved in a viewing distance w1 conditioned by a distance s1 in the prior art. The viewer's eyes of a viewer 3 at a distance pa are indicated here as small circles.

The comparison with 6b , in which a smaller viewing distance w2 caused by a smaller distance s2 in the prior art produces a smaller perceived depth t2, makes it clear how important the physical distance s is in order to obtain the greatest possible depth impression. The puncture points of the indicated visual rays 6 each on the parallax barrier screen 2 and the grid 1 of picture elements x (i, j) are in both drawings 6a and 6b at the same location, ie at the same picture elements x (i, j) and at the exact same positions of the transparent sections. By contrast, it is now possible by means of the inventive solution to resolve the relationship between w and s and despite a large distance s to reduce the viewing distance w, as with 5 was illustrated. However, the relatively large depth impression remains.

In 7 is a scheme for dimensioning the parallax barrier screen 2 shown. Where a is the angle of inclination of the transparent or opaque sections with respect to the vertical, e is the width of said sections in the horizontal direction of the screen with the picture elements x (i, j), l their height, ze their horizontal period and finally zl their vertical period ,

For further illustration of an exemplary arrangement for carrying out the method according to the invention are again the drawings 1 to 7 , So first, point 1 the schematic Structure for implementing the arrangement. This includes image display device 1 with pixels x (i, j) in a raster (i, j) with rows i and columns j, on which partial image information of different views A (k) with k = 1, ..., n and n> = 2 are made visible can be made visible on each pixel x (i, j) only the image part information of exactly one of the views A (k).

The image display device 1 from picture elements x (i, j) is at a distance s in the viewing direction of a viewer 3 at least one optical element 2 upstream or downstream of substantially periodically arranged optical structures, which predefines propagation directions for the light transmitted or emitted by the picture elements x (i, j). In this example, exactly one optical element 2 present, which as parallax barrier screen 2 is executed. Needless to say, there are also several viewers 3 be, who gain a spatial impression due to the method according to the invention.

Further shows 2 the section of a parallax barrier screen 2 for exemplary use in the inventive arrangement. This parallax barrier screen 2 contains alternately opaque and transparent sections, the transparent sections preferably corresponding to substantially rectilinear lines. The transparent and opaque sections are arranged periodically recurring, they are the optical structures on the parallax barrier screen 2 , Now, their average horizontal and vertical minimum period length is an integer multiple of the average horizontal and vertical dimensions of a pixel x (i, j) multiplied by a correction factor f, where the correction factor f is a function of a selectable viewing distance w and the mean distance s between the parallax 2 and the image display device 1 is calculated with the picture elements x (i, j), so that one or more observers 3 looking at the image display device 1 due to the optical effect of the parallax barrier screen 2 in each case with two eyes exclusively or substantially different picture elements x (i, j) and / or parts thereof see or see, whereby both eyes respectively exclusively or substantially different views A (k) perceive and thus creates a spatial visual impression.

For the design of the optical element as a parallax barrier screen 2 the following details are favorable:
In order to arrive at practically manufacturable arrangements, there is the parallax barrier screen 2 preferably from a glass substrate, on which the barrier structure is applied to the rear side. Preferably, the barrier structure is now an exposed and developed photographic film laminated on the backside of the glass substrate, preferably the emulsion layer of the photographic film facing the glass substrate.

Furthermore, the parallax barrier screen contains 2 advantageous means for reducing Störlichtreflexen, preferably at least one interference-optical anti-reflection coating. The parallax barrier screen 2 is advantageously mounted by means of a spacer permanently on the image display device, for example, glued or screwed. On the other hand, it may also be necessary to use the parallax barrier screen 2 temporarily from the image display device 1 removable.

Furthermore there 3 an example image combination of the image part information of example five different views A (k) with k = 1, ..., 5 again. In the arrangement according to the invention, the arrangement of the image part information of different views A (k) takes place on the grid 1 of pixels x (i, j) advantageously in a strictly two-dimensional periodic pattern. In the example according to 3 the horizontal period length eight and the vertical period length six pixels x (i, j), identified as a dashed frame. At the same time, the image part information for each picture element x (i, j) is derived from the position (i, j) from the corresponding view A (k).

In The exemplary embodiment presented here corresponds to the vertical period length So not the number n = 5 of the views shown.

Due to the visual confinement effect of the parallax barrier screen 2 see or see one or more viewers 3 each with two eyes substantially different picture elements x (i, j) and / or parts thereof, whereby both eyes each perceive substantially different views A (k) and thus creates a spatial visual impression. To a certain extent, the two eyes of one and the same observer can do so 3 even see partial image information of the same view A (k) without destroying the spatial impression.

henceforth The picture elements x (i, j) in this example correspond, respectively individual color subpixels (R, G or B).

The circumstances after the 1 to 3 Assuming now according to the invention are the (optimal or selected) viewing distance w and the mean distance s between the optical element 2 , so the parallax barrier screen 2 , and the image display device 1 with the grid of pixels x (i, j) independently selected. In particular, both quantities w and s are not related to one another by a predetermined value for the eye relief or / and the dimension of a pixel x (i, j), as is conventional in the prior art. The correction factor f is calculated according to the equation f = w / (w + s).

In usually in the invention, the views A (k) correspond respectively different perspectives of a scene / object. But it can also parallel projections of a scene or otherwise projected Be views.

The angle which spans the said horizontal and vertical period length of the said two-dimensional periodic pattern as counter and adjacent part essentially corresponds to the angle of inclination a (see FIG 2 ) of the transparent portions on the parallax barrier screen 2 opposite the vertical. In 3 For example, the opposing catheter could be defined by the lower horizontal dashed line and the adjacent catheter by the right vertical dashed line.

In order to will usually be the best channel separation in 3D rendering reached.

In 4 is an illustration of the effect according to the invention to see in which the viewing distance w is increased over the prior art.

In this case - without this being directly recognizable from the drawing - for the viewing distance w of one or more observers 3 , the mean distance s between the parallax barrier screen 2 and the grid 1 from picture elements x (i, j), the average pupil distance pa, and the average horizontal dimension ha of a picture element x (i, j), the inequality s / ha <w / pa. By means of the dashed lines is indicated how the conditions would be in the prior art. There the inequality would not apply, and the viewing distance would be smaller.

In contrast, in 5 to see an illustration of the effect according to the invention, in which the viewing distance w of one or more observers 3 is reduced compared to the prior art.

This results in particular advantages of the invention. In this case - without this being immediately apparent from the drawing - for the viewing distance w, the mean distance s between the parallax barrier screen 2 and the grid 1 From pixels x (i, j), the average pupillary distance pa and the average horizontal dimension ha of a pixel x (i, j), the inequality s / ha> w / pa. In this application, namely the Parallaxenbarriereschirm 2 at a relatively large distance s from the image display device 1 be arranged with the grid of picture elements x (i, j). The embodiment of the correction factor f according to the invention then ensures that a practically acceptable viewing distance w is nevertheless realized, without having to make any manipulations on the image content, for example the mixing of partial image information of several views in a picture element x (i, j).

Also here is indicated by the dashed lines, as the circumstances in the prior art. It is clearly seen that the arrangement according to the invention the viewing distance w reduces it to a practically relevant area.

The 6a and 6b each show a sketch to explain the increase of the depth impression in the case of reducing the viewing distance. It is in 6a to see how a large perceived depth t1 is achieved in a viewing distance w1 conditioned by a distance s1 in the prior art.

The viewer's eyes of a viewer 3 at a distance pa are indicated here as small circles.

The comparison with 6b , in which a smaller viewing distance w2 caused by a smaller distance s2 in the prior art produces a smaller perceived depth t2, makes it clear how important the physical distance s is in order to obtain the greatest possible depth impression. The puncture points of the indicated visual rays 6 each on the parallax barrier screen 2 and the grid 1 of picture elements x (i, j) are in both drawings 6a and 6b at the same location, ie at the same picture elements x (i, j) and at the exact same positions of the transparent sections. In contrast, it is now possible by virtue of the inventive solution, the relationship between w and s on solve and despite a large distance s to reduce the viewing distance w, as in 5 was illustrated. Nevertheless, as desired, the relatively large depth impression is retained.

In 7 a scheme for dimensioning the parallax barrier screen is shown. Where a is the angle of inclination of the transparent or opaque sections with respect to the vertical, e is the width of said sections in the horizontal direction of the screen with the picture elements x (i, j), l their height, ze their horizontal period and finally zl their vertical period ,

Exemplary now comes as a picture display device 1 an 8.4 "LCD screen with color subpixels (R, G, B) as picture elements x (i, j), where the height of the picture elements x (i, j) is about 0.1665 mm and the width ha is about 0 , 0555 mm. The transparent sections of the parallax barrier screen 2 have an inclination angle a = 23.96248897 ° relative to the vertical. The width e of said sections in the horizontal direction of the grid with the picture elements x (i, j) is 0.1109054 mm and their height 1 = 0.249537 mm. Further, the horizontal period ze = 0.4436216 mm and the distance s = 1.91 mm, the viewing distance is w = 800 mm. Finally, the vertical period of the transparent portions zl = 0.998148 mm. This means that a shortening of the viewing distance was carried out here because the inequality s / ha> w / pa is satisfied, whereby an average pupillary distance pa in humans between regularly 55 mm and 70 mm is to be expected in the inequality. In the prior art, the distance s = 0.68308 mm would have to be implemented in the aforementioned conditions for a viewing distance of w = 800 mm, which is technically and practically only very expensive to implement. Thanks to the invention, this is not necessary.

The Advantages of the invention are versatile. In particular, allow that inventive method and the corresponding arrangements an autostereoscopic display, in terms of hardware, the 3D viewing distance despite certain mechanical constraints for one Minimum distance from optical element to the screen or grid set as desired from picture elements can be. In case of decreasing the viewing distance can even the relative depth perceptions are increased.

The Invention can be realized with very simple means, in the use of Parallaxenbarriereschirmen need only the Barrier structure slightly changed be, in the production process for a corresponding 3D screen does not change anything.

Claims (12)

Method for shortening or extending a viewing distance between the viewer and the arrangement of a spatially perceptible representation, in which - on a grid ( 1 ) from picture elements x (i, j) with lines i and columns j picture part information of different views A (k) with k = 1, ..., n and n> = 2 are made visible, whereby on each picture element x (i, j ) only a partial image information of exactly one of the views A (k) is made visible, and 1 ) from picture elements x (i, j) at a distance s at least one optical element ( 2 ) is arranged upstream or downstream of periodically arranged optical structures which determine the propagation directions for the light transmitted or emitted by the picture elements x (i, j), the average horizontal and / or vertical smallest period length or a multiple thereof of the optical structures the at least one optical element ( 2 ) is an integer multiple of the average horizontal and / or vertical dimension of a picture element x (i, j) multiplied by a correction factor f, wherein the correction factor f is a function of a selectable viewing distance w and the mean distance s between the at least one optical element ( 2 ) and the grid ( 1 ) is calculated from pixels x (i, j), so that one or more observers ( 3 ) looking at the grid ( 1 ) due to the optical effect of the at least one optical element ( 2 ) each with two eyes exclusively or predominantly different pixels x (i, j) and / or parts thereof see or see, whereby both eyes respectively exclusively or predominantly different views A (k) perceive and thus creates a spatial visual impression, characterized that the viewing distance w is shortened by setting the inequality s / ha> w / pa, wherein the average horizontal dimension ha of a picture element x (i, j), the average distance s between the at least one optical element ( 2 ) and the grid ( 1 ) from picture elements x (i, j) as well as the mean pupil distance pa are not changed, however, by specific modification of the correction factor f the average decreasing the viewing distance w by adjusting the inequality s / ha <w / pa, the average horizontal dimension ha of a picture element x (i, j), the mean distance s between the at least one optical element ( 2 ) and the grid ( 1 ) of pixels x (i, j) as well as the average pupillary distance pa are also not changed, however, by targeted modification of the correction factor f, the average horizontal smallest period length of the optical structure is increased. Method according to claim 1, characterized in that that the correction factor f is calculated according to the equation f = w / (w + s). Method according to one of the preceding claims, characterized in that the picture elements x (i, j) are color subpixels (R, G or B) or clusters of color subpixels (eg RG or GB) or Full color pixels match. Method according to one of the preceding claims, characterized in that as an optical element ( 2 ) a parallax barrier screen is used which comprises transparent and opaque sections as optical structures. Method according to one of claims 1 to 3, characterized in that as an optical element ( 2 ) A lenticular screen is used, wherein the optical structures are realized by appropriate arrangement of the cylindrical lenses. Method according to claim 4, characterized in that that the transparent sections are smooth, wavy or stepped Correspond to lines with an angle of inclination a to the Vertical are inclined. Method according to claim 5, characterized in that that the cylindrical lenses with an angle of inclination a to the Vertical inclined to be arranged. Method according to one of the preceding claims, characterized characterized in that the assignment of the image part information of various Views A (k) to the pixels x (i, j) in a two-dimensional periodic pattern is carried out, wherein preferably the period length in the horizontal and vertical direction no more than respectively 32 pixels x (i, j). Method according to claim 8, characterized in that that the vertical period length is equal to the number n of views shown. Method according to one of the preceding claims, characterized in that as a picture display device ( 1 ) a color LCD screen, a plasma display, a projection screen, an LED-based screen, an OLED-based screen, an SED screen or a VFD screen is used. Method according to one of the preceding claims, characterized in that the number n of views A (k) is equal to 4, 5, 6, 7, 8 or 9 and the said horizontal period length is n picture elements x (i, j) corresponds. Method according to claim 1, characterized in that as picture display device ( 1 ) an 8.4 "LCD screen with color subpixels (R, G, B) is used as picture elements x (i, j), the height of the picture elements x (i, j) being about 0.1665 mm and the width being about 0 , 0555 mm, the image part information of various views A (k) are arranged as follows, x (i, j) 1 2 3 4 5 6 7 8th 9 ... 1 A (1) A (1) A (2) A (3) A (3) A (4) A (5) A (5) A (1) ... 2 A (2) A (2) A (3) A (4) A (4) A (5) A (5) A (1) A (2) ... 3 A (2) A (3) A (4) A (4) A (5) A (1) A (1) A (2) A (2) ... 4 A (3) A (4) A (5) A (5) A (1) A (1) A (2) A (3) A (3) ... 5 A (4) A (5) A (5) A (1) A (2) A (2) A (3) A (4) A (4) ... 6 A (5) A (1) A (1) A (2) A (2) A (3) A (4) A (4) A (5) ... 7 A (1) A (1) A (2) A (3) A (3) A (4) A (5) A (5) A (1) ... ... ... ... ... ... ... ... ... ... ... ... , wherein the following quantities are set such that the transparent portions of the parallax bar screen ( 2 ) have an inclination angle α = 23.96248897 ° with respect to the vertical, the width e of said sections in the horizontal direction of the grid with the picture elements x (i, j) is 0.1109054 mm and their height 1 = 0.249537 mm, and finally, the horizontal period ze = 0.4436216 mm, the distance s = 1.91 mm, the viewing distance w = 800 mm and the vertical period zl = 0.998148 mm of the transparent sections.